World Anti-Doping Agency officials say "points still need to be ironed out" before they are given full access to a suspended Moscow anti-doping laboratory.

Wada ended a three-year suspension of Russia in September, following a scandal over state-sponsored doping.

But a key condition was that access be given to the Moscow lab and its data.

Wada says it is aiming to carry out a "full technical mission" at the laboratory by the end of the year.

"We had open and productive meetings with the Russian public authorities," said Wada's science director Dr Olivier Rabin.

"Progress is being made but some points still need to be ironed out before we can proceed with the technical visit.

"For Wada, the sooner we can gain full access to the laboratory, the better. Clearly, there is a huge volume of data contained within it and we want to start analysing it as soon as possible."

He added the data at the laboratory was the "missing piece of the puzzle" regarding the country's doping scandal, which led to its athletes being banned from international competition.

"Once the data has been fully assessed and verified to be authentic, we would be in a position to assert anti-doping rule violations against those athletes who cheated and to exonerate other athletes," added Rabin.